Leak-free american football

ABSTRACT

Provided is a leak-free American football, which has a polyurethane foam having a shape of an American football; a covering formed on an exterior surface of the polyurethane foam and having a seam; multiple pairs of lacing holes formed in the covering along two opposite sides of the seam, and a lace passing through the multiple pairs of the lacing holes to close the seam, such that the polyurethane foam is covered by the covering and the lace. Since the polyurethane foam is solid and elastic, the leak-free American football can maintain a desired size, shape and bounce without the need for inflation, thereby improving the stability and durability.

CROSS-REFERENCE TO RELATED APPLICATION

Pursuant to 35 U.S.C. §119(a), this application claims the benefit of the priority to China Patent Application No. 201220472209.4, filed Sep. 17, 2012. The content of the prior application is incorporated herein by its entirety.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a leak-free American football, and more particularly to a leak-free American football filled with a polyurethane foam.

2. Description of the Prior Arts

With reference to FIG. 3, an inflatable sports ball, such as an American football, typically comprises a covering 31, an adhesion layer 32, an outer rubber covering 33, a yarn layer 34, an inner bladder 35, a pair of lacing holes 36, a seam 37 and a lace 38. The covering 31 is adhered onto an exterior surface of the outer rubber covering 33 by the adhesion layer 32. Since the inner bladder 35 is formed with an internal space A for pumping gas into the sports ball, the conventional sports ball can be enlarged or shrunk by inflation or deflation.

However, there are several disadvantages for the conventional inflatable sports ball. For instance, sufficient gas is required to sustain the shape and the size of the sports ball. If the pressure in the inner bladder is varied, the conventional sports ball may lose the desired size, shape and bounce. The touch and elasticity thus cannot be kept steady, such that the players can hardly handle the sports ball.

Moreover, if the inflatable sports ball is pierced by a needle or any sharp-pointed object, the gas pumped in the sports ball will be leaked out and the sports ball is deformed. As a result, the sports ball is broken and cannot bounce normally.

To overcome the aforementioned shortcomings, the present invention provides a leak-free American Football filled with a polyurethane foam to mitigate or obviate the aforementioned problems.

SUMMARY OF THE INVENTION

A primary objective of the present invention is to provide a leak-free American football having enhanced stability and durability to overcome the drawbacks of a conventional inflatable American football.

To achieve the objective, the leak-free American football of the present invention has a polyurethane foam (PU foam) having a shape of an American football; a covering formed on an exterior surface of the polyurethane foam and having a seam; multiple pairs of lacing holes, each pair of the lacing holes formed in the covering respectively along two opposite sides of the seam, and a lace passing through the multiple pairs of the lacing holes to close the seam, such that the polyurethane foam is covered by the covering and the lace.

Preferably, the polyurethane foam has elasticity and a density ranging from 85 kg/m³ to 200 kg/m³ for sustaining the leak-free American Football's desired bounce. Accordingly, the drawbacks resulted from pressure variation and reliance on inflation are overcome. More preferably, the polyurethane foam has a density ranging from 85 kg/m³ to 105 kg/m³.

Preferably, the polyurethane foam of the leak-free American football has a hardness ranging from 40 Shore A to 70 Shore A.

Accordingly, based on a same size, the leak-free American football in accordance with the present invention has a weight, elasticity, softness, and touch same with or close to those of the conventional inflatable American football.

Preferably, the covering has a thickness ranging from 0.6 to 3.0 millimeters.

Preferably, the covering includes a first section formed on the exterior surface and a second section formed on the exterior surface and adjacent to the first section, the seam is formed between the first section and the second section, a part of the lacing holes are formed in the first section along one of the two opposite sides of the seam, and the other lacing holes paired with said part of the lacing holes are formed in the second section along the other side of the seam, and positions of the lacing holes formed in the first section correspond to positions of the lacing holes formed in the second section.

Preferably, the lace has two ends opposite to each other and a lacing body formed between the ends, the lacing body of the lace passes through the multiple pairs of the lacing holes, and the ends of the lace are inserted into the seam and between the lacing body of the lace and the polyurethane foam. Accordingly, the lace can be used to close the seam and sustain a desired tightness of the leak-free American football. Furthermore, the lace is used for improving gripping and passing of the leak-free American football during playing.

Preferably, the leak-free American football can further have a pattern on the covering.

Preferably, the shapes of the leak-free American football and the polyurethane foam are substantially prolate spheroidal.

Preferably, the covering of the leak-free American football can be made of polyvinyl chloride leather, polyurethane leather, microfiber leather or cow leather.

Preferably, the polyurethane foam is made in an integral configuration and is directly covered by the covering and the lace.

Preferably, the covering is adhered to the exterior surface of the polyurethane foam with an adhesion agent. An adhesion layer is formed between the polyurethane foam and the covering.

Other objectives, advantages and novel features of the invention will become more apparent from the following detailed description when taken in conjunction with the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of a leak-free American football in accordance with the present invention.

FIG. 2 is a sectional view of the leak-free American football with polyurethane foam in accordance with the present invention.

FIG. 3 is a sectional view of a conventional inflatable American football in accordance with the prior art.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Hereinafter, one skilled in the arts can easily realize the advantages and effects of the present invention from the following embodiments. The descriptions proposed herein are just preferable embodiments for the purpose of illustrations only, not intended to limit the scope of the invention. Various modifications and variations could be made in order to practice or apply the present invention without departing from the spirit and scope of the invention.

Preparation Example

The raw material used for manufacturing the polyurethane foam of the leak-free American football in accordance with the present invention comprises, for example, but not limited to:

-   -   (1) main materials:         -   i. polyurethane; and         -   ii. isocyanate.     -   (2) additive material:         -   i. cross linking reagent:             -   ethylene glycol, diethanol amine or dipropylene glycol;         -   ii. foaming agent:             -   tannous octanoate or water;         -   iii. stabilizing reagent:             -   silicone oil;         -   iv. catalysts:             -   butanediol amine or N,N-dimethylethanol amine; and         -   v. solvent:             -   water or methylene chloride (MC).

The method for manufacturing the leak-free American football in accordance with the present invention was implemented as follows. In one embodiment of the present invention, a leak-free American football was manufactured.

First, the main material was mixed with the aforementioned additive materials to obtain a pre-mixture. According to the present embodiment, the weight ratio of polyurethane to isocyanate was 100:68, the molecular weight of the polyurethane ranged from 3000 to 12000 g/mole, and the respective amount of each additive material ranged from 0.001 to 25 kilograms per 100 kilograms of the main material.

Before injection molding, a mold with a shape of an American football (i.e. prolate spheroid) was provided and cleaned. A commercially available release reagent was applied to the inner surface of the cleaned mold, and then the cleaned mold was pre-heated to 50° C. for molding.

Next, the pre-mixture was injected into a foam dispensing equipment with a flux of 100 grams/second for about 3-4 seconds. Subsequently, the pre-mixture was further supplied into the aforementioned pre-heated mold, and cured in the mold for 4-6 minutes. After a polyurethane foam was injection molded, the polyurethane foam with a corresponding shape was released from the mold to produce a polyurethane foam of the leak-free American football.

Subsequently, a covering made of polyurethane leather was provided and further printed with a trademark or logo thereon. Said covering comprises a first section, a second section, a third section and a fourth section. The first section and the second section were formed with multiple pairs of lacing holes near their edges. Glue was applied to an exterior surface of the polyurethane foam and interior surfaces of the aforementioned sections to respectively adhere the first, second, third and fourth sections onto the exterior surface of the polyurethane foam, such that an adhesion layer was formed between the covering and the polyurethane foam. Said first section and second section were disposed adjacent to each other, and the lacing holes formed in the first section were also arranged along the lacing holes formed in the second section. After adhering the aforementioned sections onto the polyurethane foam, a seam was formed between the first section and the second section.

Then, a lace was passed through the multiple pairs of the lacing holes to close the seam. Accordingly, a leak-free American football was manufactured.

Examples 1 and 2

Two leak-free American footballs in Examples 1 and 2 were manufactured by the method as described in aforementioned Preparation Example. Both of the two leak-free American footballs have a similar structure as described below, and the difference between them is their sizes.

With reference to FIGS. 1 and 2, the leak-free American football 1 in accordance with the present invention is prolate spheroidal in shape. Said leak-free American football has a polyurethane foam 11, an adhesion layer 12, a covering 13, multiple pairs of lacing holes 14 and a lace 15.

The covering 13 is adhered onto an exterior surface of the polyurethane foam 11 by the adhesion layer 12 and has a first section 131, a second section 132, a third section 133 and a fourth section 134. Said first section 131 is disposed adjacent to the second section 132, and a seam 16 is formed between the first section 131 and the second section 132.

The multiple pairs of the lacing holes 14 are formed near the seam 16 and classified into two parts according to their locations. One of the two parts of the lacing holes 141 are formed in the first section 131 of the covering 13, and the other lacing holes 142, which are respectively paired with said part of the lacing holes 141, are formed in the second section 132 of the covering 13. The lacing holes 141 formed in the first section 131 are located at positions corresponding to those of the lacing holes 142 formed in the second section 132.

The lace 15 has two ends opposite to each other and a lacing body formed between the ends. The lacing body passes through the multiple pairs of the lacing holes 141, 142, and the ends of the lace 15 are inserted into the seam 16 and between the lacing body of the lace 15 and the polyurethane foam 11 to close the seam 16 and sustain a desired tightness of the leak-free American football. Accordingly, the polyurethane foam 11 is covered by the covering 13 and the lace 15.

Hereinafter, the long circumferences (measured across the lace), long circumferences (measured without the lace), short circumferences, the heights, the weights, and the hardness and the densities of the leak-free American footballs in Example 1 and 2 are measured and listed on Table 1. The official standard size of a conventional inflatable American football and characteristics are also listed in Table 1 for comparison.

TABLE 1 characteristics of the leak-free American footballs in Examples 1 and 2 and the conventional inflatable American football. Leak-free Leak-free conventional inflatable American American American football with football in football in Official Standard Size Example 1 Example 2 long 705-717 mm 712 mm 710 mm circumference (measured across lace) long 701-709 mm 704 mm 701 mm circumference (measured without across lace) short 524-531 mm 529 mm 530 mm circumference Height 278-285 mm 283 mm 282 mm Weight 397-425 grams 423 grams 422.5 grams Hardness 63 Shore A 55 Shore A 55 Shore A Density 85 kg/m³ 105 kg/m³ 85 kg/m³ 105 kg/m³

As shown in Table 1, based on a same size, a leak-free American football 1 enclosed with a solid and elastic polyurethane foam 11 of the present invention has a weight and a density close to those of the conventional inflatable American football. The results demonstrated that both the leak-free American footballs 1 in Examples 1 and 2 can meet the requirements of the size, weight and density based on the Official Standard American football.

In summary, the integral polyurethane foam 11 of the present invention replaces an inner bladder, a yarn layer and an outer rubber covering of a conventional inflatable American football to be the core portion of the leak-free American football. Since the polyurethane foam 11 filled in the leak-free American football 1 is solid and elastic, it can sustain a desired size, shape and bounce of the leak-free American football without the need for inflation, and successfully overcome the problems including leakage or deformation. Consequently, the stability and the durability of the leak-free American football 1 of the present invention are significantly enhanced.

Even though numerous characteristics and advantages of the present invention have been set forth in the foregoing description, together with details of the structure and features of the invention, the disclosure is illustrative only. Changes may be made in the details, especially in matters of shape, size, and arrangement of parts within the principles of the invention to the full extent indicated by the broad general meaning of the terms in which the appended claims are expressed. 

What is claimed is:
 1. A leak-free American football, having: a polyurethane foam having a shape of an American football; a covering formed on an exterior surface of the polyurethane foam and having a seam; multiple pairs of lacing holes, each pair of the lacing holes formed in the covering respectively along two opposite sides of the seam, and a lace passing through the multiple pairs of the lacing holes to close the seam, such that the polyurethane foam is covered by the covering and the lace.
 2. The leak-free American football as claimed in claim 1, wherein the polyurethane foam has a density ranging from 85 kg/m³ to 200 kg/m³.
 3. The leak-free American football as claimed in claim 2, wherein the polyurethane foam has a density ranging from 85 kg/m³ to 105 kg/m³.
 4. The leak-free American football as claimed in claim 1, wherein the polyurethane foam has a hardness ranging from 40 Shore A to 70 Shore A.
 5. The leak-free American football as claimed in claim 2, wherein the polyurethane foam has a hardness ranging from 40 Shore A to 70 Shore A.
 6. The leak-free American football as claimed in claim 3, wherein the polyurethane foam has a hardness ranging from 40 Shore A to 70 Shore A.
 7. The leak-free American football as claimed in claim 1, wherein the covering has a thickness ranging from 0.6 to 3.0 millimeters.
 8. The leak-free American football as claimed in claim 3, wherein the covering has a thickness ranging from 0.6 to 3.0 millimeters.
 9. The leak-free American football as claimed in claim 4, wherein the covering has a thickness ranging from 0.6 to 3.0 millimeters.
 10. The leak-free American football as claimed in claim 1, wherein the shape of the American football is substantially prolate spheroidal.
 11. The leak-free American football as claimed in claim 1, wherein the covering is made of polyvinyl chloride leather, polyurethane leather, microfiber leather or cow leather.
 12. The leak-free American football as claimed in claim 1, wherein an adhesion layer is formed between the covering and the polyurethane foam for adhering the covering onto the exterior surface of the polyurethane foam.
 13. The leak-free American football as claimed in claim 1, wherein the covering includes a first section formed on the exterior surface and a second section formed on the exterior surface and adjacent to the first section, the seam is formed between the first section and the second section, a part of the lacing holes are formed in the first section along one of the two opposite sides of the seam, and the other lacing holes paired with said part of the lacing holes are formed in the second section along the other side of the seam, and positions of the lacing holes formed in the first section correspond to positions of the lacing holes formed in the second section.
 14. The leak-free American football as claimed in claim 13, wherein the lace has two ends opposite to each other and a lacing body formed between the ends, the lacing body of the lace passes through the multiple pairs of the lacing holes, and the ends of the lace are inserted into the seam and between the lacing body of the lace and the polyurethane foam.
 15. The leak-free American football as claimed in claim 1, wherein the leak-free American football has a pattern on the covering.
 16. The leak-free American football as claimed in claim 6, wherein the shape of the American football is substantially prolate spheroidal.
 17. The leak-free American football as claimed in claim 15, wherein the covering is made of polyvinyl chloride leather, polyurethane leather, microfiber leather or cow leather.
 18. The leak-free American football as claimed in claim 16, wherein the covering includes a first section formed on the exterior surface and a second section formed on the exterior surface and adjacent to the first section, the seam is formed between the first section and the second section, a part of the lacing holes are formed in the first section along one of the two opposite sides of the seam, and the other lacing holes paired with said part of the lacing holes are formed in the second section along the other side of the seam, and positions of the lacing holes formed in the first section correspond to positions of the lacing holes formed in the second section.
 19. The leak-free American football as claimed in claim 18, wherein the lace has two ends opposite to each other and a lacing body formed between the ends, the lacing body of the lace passes through the multiple pairs of the lacing holes, and the ends of the lace are inserted into the seam and between the lacing body of the lace and the polyurethane foam.
 20. The leak-free American football as claimed in claim 19, wherein an adhesion layer is formed between the covering and the polyurethane foam for adhering the covering onto the exterior surface of the polyurethane foam. 